MILLVILLE — Environmental groups will protest Thursday against what they say is a decision by the state that could cause “intensive development” by allowing new sewer lines through the so-called Wawa Tract.

The groups said in a statement released Monday that the state Department of Environmental Protection decision runs counter to an earlier policy by the department that bans new sewer lines through the almost 400-acre tract.

“The rules were designed to protect water by prohibiting the extension of sewer lines into lands that protect water quality and avoid the water degradation impacts of intense development that follows sewers,” the statement reads.

The Wawa Tract covers an area loosely bordered by Sharp Street and routes 47 and 55. The tract has almost a mile of shoreline along Union Lake.

American Littoral Society, Citizens United to Protect the Maurice River, the New Jersey Conservation Foundation, Association of New Jersey Environmental Associations, and the South Jersey Land and Water Trust issued the statement. Representatives of those groups are scheduled to speak during Thursday’s event.

DEP spokesman Larry Hajnacq said the sewer extension ban was based on old information that showed the Wawa Tract was a suitable habitat for pine snakes. New information provided by the city and the Wawa Tract developer, with which DEP staff concur, shows that is not the situation, he said.

The change was driven by the city and developer, Hajna said. DEP now does “not have justification in our rules to exclude” the Wawa Tract from the sewer extension ban, he said.

“We have to follow the regulations,” he said.

Development of the Wawa Tract has been a source of controversy for almost a decade.

Housing developer Matzel and Mumford, a K. Hovnanian company, originally planned to build 1,200 homes. That number eventually decreased to 532 single-family homes.

Matzel and Mumford then abandoned the plan in 2008 after the housing crash that accompanied the national economic downtown. City officials began working on a new plan for the site.

The resulting plan adopted in April 2011 called for 210 acres of the wooded tract to be designated for open space. Wawa representatives previously gave the city a development map that included much less open space.

The plan also allocates 85 acres for a new shopping center, 57 acres for homes, 13 acres for a new elementary school and athletic fields behind Lakeside Middle School, 12 acres for an office park and four acres for historic preservation.

That plan was developed with input from the five groups holding Thursday’s events. Officials with the American Littoral Society lauded the city for a plan that they said was “environmentally sensitive.”

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